Hinge

ABSTRACT

The hinge comprises a compression spring for balancing the weight of leaves which are hinged on a horizontal axis, such as covers, flaps or the like, particularly in refrigerating chests. One end of the compression spring bears under initial stress on the stationary hinge member. The other end of the spring bears by means of the end of a spring-guiding rod, which supports the spring, on the second hinge member, which is secured to the leaf. The lower end of the spring-guiding rod bears by means of a rocker on a knife edge bearing provided on the stationary hinge member. The guiding rod is provided with coarse pitch screw threads at its end opposite to the slider. The rocker carries a nut which has coarse pitch screw threads and is in threaded engagement with the lower end of the guiding rod.

[ Dec. 23, 1975 HINGE [76] Inventor: Wilhelm Gronbach, Dr. FritzHuber-Strasse No. 73, 8090 Wasserburg, Germany 22 Filed: Feb. 20, 197421 Appl. No.: 444,116

[30] Foreign Application Priority Data Feb. 20, 1973 Germany 2308361Apr, 6, 1973 Germany 2317397 May 7, 1973 Germany 2322967 [52] US. Cl.16/190 [51] Int. Cl. A47H 15/00 [58] Field of Search 16/190, 145, 180

[5 6] References Cited UNITED STATES PATENTS 2,911,667 11/1959 Burke16/190 FOREIGN PATENTS OR APPLICATIONS 2,030,784 11/1970 France 16/190Primary Examiner-Paul R. Gilliam Assistant ExaminerDoris L. TroutmanAttorney, Agent, or Firm-Fleit & Jacobson [57] ABSTRACT The hingecomprises a compression spring for balancing the weight of leaves whichare hinged on a horizontal axis, such as covers, flaps or the like,particularly in refrigerating chests. One end of the compression springbears under initial stress on the stationary hinge member. The other endof the spring bears by means of the end of a spring-guiding rod, whichsupports the spring, on the second hinge member, which is secured to theleaf. The lower end of the springguiding rod bears by means of a rockeron a knife edge bearing provided on the stationary hinge member. Theguiding rod is provided with coarse pitch screw threads at its endopposite to the slider. The rocker carries a nut which has coarse pitchscrew threads and is in threaded engagement with the lower end of theguiding rod.

8 Claims, 4 Drawing Figures US. Patent Dec.23, 1975 Sheet 1 of23,927,439

US. Patent Dec. 23, 1975 Sheet 2 of2 HINGE This invention relates to'ahinge which comprises a compression spring for balancing the weight ofleaves which are hinged on a horizontal axis, such as covers, flaps orthe like, particularly in refrigerating chests, in which hinge one endof the compression spring bears under initial stress on the stationaryhinge member, the other end of the spring bears by means of the end of aspring-guiding rod, which supports the spring, on the second hingemember, which is secured to the leaf, and the lower end of thespring-guiding rod bears by means of a rocker on a knife edge bearingprovided on the stationary hinge member.

A hinge of this kind has been disclosed in the Germa PatentSpecification No. 1,708,350. In that known hinge, the spring-guiding rodcarries at its upper end a slider, which consists of polyacetal resin ora material having similar properties and is guided by a cam face, whichcomprises a control cam face portion and a stressing cam face portion.Such hinge is designed to compensate the cosine-shaped turning moment ofthe cover throughout its opening movement. For this compensation, thespring force and spring characteristic must match the turning moment ofthe cover within fairly close limits. For this reason, different springsare required, which correspond to cover turning moments differing byincrements of l kilogram-meter.

It is an object of the invention to enable a control of the coverturning moments to be expected by springs in a number which is reducedpreferably to one-third.

In a hinge of thekind described first hereinbefore, this object isaccomplished according to the invention in that the guiding rod isprovided with coarse pitch screw threads at its lower end and that therocker carries a nut which has coarse pitch screw threads and is inthreaded engagement with the lower end of the guiding rod. In theabsence of the cam face comprising a control cam face portion and astressing cam face portion in accordance with the German PatentSpecification No. 1,708,350 a balancing of weights can be ensured onlyin a single position. Owing to the design of the lower end of theguiding rod, the hinge in accordance with the invention enables abalancing of weight in a larger range, which depends in each case on thethickness of the spring or springs and the weight of the leaf. The hingeaccording to the invention has the further advantage that the number ofsprings to be kept on stock by the buyer are reduced. Besides, the needof adjusting the known'hinge to the actual cover turning moment isentirely eliminated.

When it is essential that the function of the hinge should reach thecosine-shaped turning moment of the cover as soon as possible andcompensates the samethroughout the opening movement, it is contemplatedaccording to the invention to provide the spring-guiding rod at itsupper end with a slider, which consists of polyacetal resin or amaterial having similar properties and is guided by a cam face whichcomprises a control cam face portion and a stressing cam face portionand which is directly provided in the hinge member that is secured tothe leaf. I

According to another feature of the invention, the coarse pitch screwthreads are multiple threads. These have the advantage of providing fora contact on alarge surface so that the desired function is maintainedindefinitely in spite of the pressure contact between the faces of thethreads during a displacement of the spring-guiding rod in itslongitudinal direction.

According to a further feature of the invention, the coarse pitch nut ismade of plastics material, preferably of polyacetal resin. Such coarsepitch nut does not take up moisture and for this reason is dimensionallystable. Besides, the nut resists oil and acid and in spite of its goodclamping action is highly slidable.

In a particularly preferred embodiment of the invention the coarse pitchnut is held against rotation in the rocker and a washer is providedbetween the nut and the lower end of the spring. With this design, thewasher acts as a brake during a longitudinal movement of the guiding rodbecause the washer is carried along by the spring and the latter isrotated by the guiding rod owing to the frictional engagement.

The hinge according to the invention may be provided with a double brakeif this is required. For this purpose it is a feature of the inventionthat the guiding rod is provided adjacent to the upper end of the springwith a bushing that consists of plastics material, preferably ofpolyacetal resin, and has an upper annular flange, which is embeddedbetween two washers, the upper one of which bears on retaining cams onthe guiding rod whereas the lower washer bears on the upper end of thespring.

In a particularly desirable embodiment of the invention the sliderprovided at the upper end of the springguiding rod and consisting ofpolyacetal resin or a material having similar properties has a curvedrecessed bearing surface, which engages a pin mounted in the second,movable hinge member. Because the upper end of the spring-guiding roddoes not bear directly on a pivot pin mounted in the second hing memberbut a sliding surface bearing having a recessed curved bearing surfaceis interposed, a canting at the bearing is avoided whereas such cantingis otherwise inevitable owing to manufacturing tolerances. Besides,there can be no frictional resistance due to such canting at thebearing.

In a development of the invention opposite ends of the pivot pin arereceived by respective recesses in mutually opposite surfaces of thestationary hinge member and these mutually opposite surfaces are shapedso as to define the two end positions of the hinge. This has theadvantage that the hinge can be covered on the outside by caps ofplastics material whereby the appearance of the hinge is improved. Thezero position of the hinge is selected so that in said position theturning moment of the cover is not opposed at all.

Two embodiments of the invention will be described hereinafter withreference to the drawing, in which FIG. 1 is a sectional view showingthe hinge according to a first embodiment of the invention,

FIG. 2 is an elevation showing the hinge according to this embodiment ofthe invention as viewed from the open side of the hinge housing,

FIG. 3 is a sectional view showing a hinge according to anotherembodiment of the invention, and

FIG. 4 is an elevation showing the hinge according to this embodiment ofthe invention as viewed from the open side of the hinge housing.

The hinge comprises a hinge member 1, which is secured to a leaf 2, anda stationary hinge member 3, which is secured to a base, e.g., of arefrigerating chest. The hinge member 3 consists of a U-shaped housing,which is open on the side facing away from the refrigerating chest, andis secured to the refrigerating chest with the aid of openings 4, 5. Themovable hinge member 1 is secured to the leaf 2 by means of bores 6 to9. It is readily apparent from FIG. 2 that the bores required for thefixation are exposed even when the hinge has been assembled so that itcan be secured quickly and in a simple manner to the base and cover ofthe refrigerating chest.

The two hinge members are hingedly interconnected by a hinge pin 10. Acam face 12 is provided directly in the hinge member 1 which is securedto the leaf 2. In the embodiment shown by way of example the cam face 12consists of a snapped-in stamping 13 of spring steel strip.

This cam face 12 serves to guide a slider 14, which consists ofpolyacetal resin and is provided with lateral guide flanges 15. Theslider 14 of polyacetal resin is mounted on the shank end 16 of aspring-guiding rod 17, which is rotatable about its axis in the slider14. 14 is a slider fitting, which consists of sheet metal and isinserted into the mold used to make the slider. This fitting is visiblein the drawing only because the slider has a groove there.

The spring-guiding rod 17 is mounted in the stationary hinge member 3 ata point which is spaced by a distance depending on the initial stress ofthe spring 18 or the springs 18, 19 from the point where the other endof the rod is pivoted. The embodiment shown by way of example comprisesa knife-edge bearing 20, which supports a rocker 21. As described thusfar, the hinge according to the invention is designed like that ofGerman Patent Specification No. 1,708,350.

According to the invention the guiding rod 17 is provided with coarsepitch screw threads 22 at the end which is remote from the slider 14. Anut 23 having coarse pitch screw threads is mounted on the rocker 21.The lower end of the spring-guiding rod 17 is threaded in the coarsepitch nut 23. In the embodiment shown by way of example the coarse pitchscrew threads are multiple screw threads having a helix angle of aboutThe specific helix angle will depend on the number of parallel threads,the area of the thread faces and on the height of the nut, i.e., on theclamping surface area. In the embodiment shown by way of example thecoarse pitch nut 23 consists of polyacetal resin. The nut is heldagainst rotation in the rocker 21. A washer 24 is provided between thenut 23 and the lower end of the spring 18 or of the springs 18, 19.

In the embodiment shown by way of example the hinge is provided with adual brake. For this purpose the spring-guiding rod 17 is providedadjacent to the upper end of spring 18 or springs 18, 19 with a bushing25 of plastics material, specifically polyacetal resin. The bushing 25has an upper annular flange 26, which is embedded between two washers27, 28. The upper washer bears on retaining cams 29, provided on thespring-guiding rod 17. The lower washer bears on the upper end of thespring 18 or springs 18, 19.

The mode of operation of the hinge according to the invention is readilyapparent from the above description of its elements or construction.FIG. 1 shows the hinge in closed condition. The stressed spring 18 orsprings 18, 19 force the slider 14 against the stressing cam faceportion 31, which by means of the hinge pin 10 exerts an additionalclosing pressure on the leaf2 of the refrigerating chest. When the leaf2 is now turned open. the relaxing spring 18 or springs 18, 19 cause theslider 14 to move along the cam face 12 so as to ensure a balancing ofmasses.

Stops 33 and 34 are provided at respective ends of the cam face 12 andcooperate with the slider 14 and with the back of the spring-guiding rod17 to define the fully open position of the leaf 2. The hinge 34 isformed by bending in the hinge member 1 itself. The fixing lugs 35, 36formed with the bores 6 to 9 are bent at right angles from the legs ofthe hinge member 1.

The hinge pin 10 is mounted in a bearing sleeve 37 between the bores 6,8 and 7, 9 of the fixing lugs 35, 36.

The coarse pitch screw threads 22 in conjunction with the coarse pitchnut 23 enable the control of the turning moments to be expected bysprings in a number which is reduced to one-third. As has been mentionedhereinbefore, there is nevertheless no need for an adjustment inadaptation to the actual turning moment.

In the embodiment shown in FIGS. 3 and 4, the hinge comprises a hingemember 101, which is secured to a leaf 102, and a stationary hingemember 103, which is secured to a base, e.g., of a refrigerating chest.The hinge member 103 consists of a U-shaped housing, which is open onthe side facing away from the refrigerating chest, and is secured to therefrigerating chest with the aid of openings 104, 105. The movable hingemember 101 is secured to the leaf 102 by means of bores 106 to 109. Itis readily apparent from FIG. 4 that the bores required for the fixationare exposed even when the hinge has been assembled so that it can besecured quickly and in a simple manner to the base and cover of therefrigerating chest.

The two hinge members are hingedly interconnected by a hinge pin 110.

The spring-guiding rod 111 is mounted in the stationary hinge member 103at a point which is spaced by a distance depending on the initial stressof the spring 112 or the springs 112, 113 from the point where the otherend of the rod is pivoted. The embodiment shown by way of examplecomprises a knife-edge bearing 114, which supports a rocker 115.

The guiding rod 111 is provided with coarse pitch screw threads 116 atthe end which is remote from the hinge pin 110. A nut 117 having coarsepitch screw threads is mounted on the rocker 115. The lower end of thespring-guiding rod 111 is threaded in the coarse pitch nut 117. In theembodiment shown by way of example the coarse pitch screw threads aremultiple screw threads having a helix angle of about 20. The specifichelix angle will depend on the number of parallel threads, the area ofthe thread faces and on the height of the nut, i,e., on the clampingsurface area. In the embodiment shown by way of example the coarse pitchnut 114 consists of polyacetal resin. The nut is held against rotationin the rocker 115. A washer 118 is provided between the nut 117 and thelower end of the spring 112 or of the springs 112, 113.

In the embodiment shown by way of example the hinge is provided with adual brake. For this purpose the spring-guiding rod 111 is providedadjacent to the upper end of spring 112 or springs 112, 113 with abushing 119 of plastics material, specifically polyacetal resin. Thebushing 119 has an upper annular flange 120, which is embedded betweentwo washers 121, 122. The upper washer bears on retaining cams 123, 124provided on the spring-guiding rod 111. The lower washer bears on theupper end of the spring 112 or springs 112, 113.

At its end opposite to the rocker 115, the springguiding rod 111 carriesa sliding-surface bearing 125, which has a recessed curved bearingsurface bearing on a pin 126, which is mounted in the second hingemember 101. Opposite ends of the pivot pin 126 are received byrespective recesses 127 in mutually opposite surfaces of the U-shapedhousing of the stationary hinge member 103. These recesses are shaped todefine the two end positions of the hinge.

The hinge pin 110 is mounted in a bearing sleeve 129 between the bores106, 108 and 107, 109 of the fixing lug 128.

The coarse pitch screw threads 116 in conjunction with the coarse pitchnut 117 enable the control of the turning moments to be expected bysprings in a number which is reduced to one-third. As has been mentionedhereinbefore, there is nevertheless no need for an adjustment inadaptation to the actual turning moment.

What is claimed is:

1. A hinge adapted to balance covers or flaps or refrigerating chests,comprising:

a stationary leaf hinge member;

a movable leaf hinge member pivotally mounted on said stationary leafhinge member;

a bearing surface on one of said hinge members displaced from thepivotal axis of said leaf hinge members;

a bearing element mounted on the other of said hinge members and ridingon said bearing surface;

a guiding-rod having an abutment stop means thereon;

first means pivotally mounting one end of said guiding-rod on thestationary leaf hinge member and including nut means fixed to saidstationary leaf hinge member with said one end of the rod beingrotatably engaged with said nut means;

second means connecting the other end of said guiding-rod to saidbearing element so that, upon opening or closing said hinge, saidbearing element, in following said bearing surface, causes saidguidingrod to move axially through said nut means while pivoting aboutsaid one end of said guiding-rod;

a pre-stressed compression spring mounted on ,said guiding-rod andbearing on one end against said abutment stop means and on the other endagainst 6 said nut means imposing an axial force on said guiding-rod;

said guiding-rod and said nut means defining mutually coacting means forbraking movement of said guiding-rod during opening and closing of saidhinge comprising a first set of coarse pitch screw threads defined onthe outer periphery of the one end of said guiding-rod, and a second setof coarse pitch screw threads defined on the internal surface of saidnut means, said sets being complementary and of the type having a helixangle in the order of 20 and being threadedly engaged forcing saidguiding-rod to undergo a rotational braking movement when moving throughsaid nut means.

2. A hinge according to claim 1, characterized in that thespring-guiding rod is provided at its abutting end with a slider, whichcomprises polyacetal resin said bearing surface further includes a camface Which comprises a control cam face portion and a stressing cam faceportion and which is secured in the hinge member that is secured to thecover.

3. A hinge according to claim 1, characterized in that the coarse screwthreads are multiple threads, preferably six-start threads.

4. A hinge according to claim 1, characterized in that the nut is madeof plastics material.

5. A hinge according to claim 1 including means for holding said nutagainst rotation in the guiding rod pivotal means and further includinga washer disposed between the nut and the lower end of the spring.

6. A hinge according to claim 1, including retaining cams on saidguiding rod and a bushing on the upper end of said guiding rod thatcomprises a plastics material, and has an upper annular flange andfurther including two washers, an upper washer which bears on saidguiding rod retaining cams and a lower washer which bears on the upperend of the spring.

7. A hinge according to claim 2, characterized in that the slider has acurved recessed bearing surface and including a pin mounted in thesecond movable hinge member.

8. A hinge according to claim 7, characterized in that opposite ends ofthe pin are received by respective recesses in mutually oppositesurfaces of the bearing surface and these mutually opposite surfaces areshaped to define two end positions of the hinge.

1. A hinge adapted to balance covers or flaps or refrigerating chests,comprising: a stationary leaf hinge member; a movable leaf hinge memberpivotally mounted on said stationary leaf hinge member; a bearingsurface on one of said hinge members displaced from the pivotal axis ofsaid leaf hinge members; a bearing element mounted on the other of saidhinge members and riding on said bearing surface; a guiding-rod havingan abutment stop means thereon; first means pivotally mounting one endof said guiding-rod on the stationary leaf hinge member and includingnut means fixed to said stationary leaf hinge member with said one endof the rod being rotatably engaged with said nut means; second meansconnecting the other end of said guiding-rod to said bearing element sothat, upon opening or closing said hinge, said bearing element, infollowing said bearing surface, causes said guiding-rod to move axiallythrough said nut means while pivoting about said one end of saidguiding-rod; a pre-stressed compression spring mounted on saidguiding-rod and bearing on one end against said abutment stop means andon the other end against said nut means imposing an axial force on saidguiding-rod; said guiding-rod and said nut means defining mutuallycoacting means for braking movement of said guiding-rod during openingand closing of said hinge comprising a first set of coarse pitch screwthreads defined on the outer periphery of the one end of saidguiding-rod, and a second set of coarse pitch screw threads defined onthe internal surface of said nut means, said sets being complementaryand of the type having a helix angle in the order of 20* and beingthreadedly engaged forcing said guiding-rod to undergo a rotationalbraking movement when moving through said nut means.
 2. A hingeaccording to claim 1, characterized in that the spring-guiding rod isprovided at its abutting end with a slider, which comprises polyacetalresin said bearing surface further includes a cam face Which comprises acontrol cam face portion and a stressing cam face portion and which issecured in the hinge member that is secured to the cover.
 3. A hingeaccording to claim 1, characterized in that the coarse screw threads aremultiple threads, preferably six-start threads.
 4. A hinge according toclaim 1, characterized in that the nut is made of plastics material. 5.A hinge according to claim 1 including means for holding said nutagainst rotation in the guiding rod pivotal means and further includinga washer disposed between the nut and the lower end of the spring.
 6. Ahinge according to claim 1, including retaining cams on said guiding rodand a bushing on the upper end of said guiding rod that comprises aplastics material, and has an upper annular flange and further includingtwo washers, an upper washer which bears on said guiding rod retainingcams and a lower washer which bears on the upper end of the spring.
 7. Ahinge according to claim 2, characterized in that the slider has acurved recessed bearing surface and including a pin mounted in thesecond movable hinge member.
 8. A hinge according to claim 7,characterized in that opposite ends of the pin are received byrespective recesses in mutually opposite surfaces of the bearing surfaceand these mutually opposite surfaces are shaped to define two endpositions of the hinge.